This type of apparatus suggested is, for example, an apparatus for controlling an electric power steering and a braking pressure of each wheel in order to achieve a target rudder angle in a lane keeping mode of a vehicle and for controlling a steering gear ratio varying apparatus in order to reduce a yaw angle deviation and a lateral position deviation of the vehicle with respect to a driving route (refer to a patent document 1).
Alternatively, another apparatus suggested is an apparatus for reducing and correcting a control amount of steering control in accordance with a steering wheel operating state and a steering wheel operating direction if a conscious steering wheel operation by a driver is detected when a rudder angle of rear wheels of the vehicle is controlled to perform the steering control of the vehicle (refer to a patent document 2).
Alternatively, another apparatus suggested is an apparatus for reducing a target control amount of a target control torque if a steering direction of the target control torque is different from a steering direction of a steering torque and if there is control interference when the steering torque is controlled by an electric power steering apparatus such that the vehicle keeps a driving lane and drives on it (refer to a patent document 3).
Alternatively, another apparatus suggested is an apparatus for steering by controlling a motor current and rotationally controlling a steering motor such that the rudder angle is equal to the target rudder angle (refer to a patent document 4). Here, in particular, it is disclosed that the motor current is reduced in accordance with an increase in the steering torque value when a direction indicated by a steering torque value of a steering wheel detected by a torque sensor is equal to a direction of the target rudder angle and that the motor current is increased in accordance with the increase in the steering torque value when the direction indicated by the steering torque value is opposite to the direction of the target rudder angle.